According to the World Health Organisation (WHO), somewhere between 25 and 50% of people may have been physically abused at some point during their childhood, an experience defined as the use of physical force that harms the child’s health, survival, development, or dignity. Childhood maltreatment does not stop at physical abuse, however – children may be emotionally or sexually abused or neglected – and these experiences can have lasting implications for the health of the adult.

The association between child sexual abuse and poor psychological health in adult life is now well established. However, the impact of exposure to non-sexual child maltreatment (physical and emotional abuse, and neglect) on long-term health outcomes has not been systematically examined.

A systematic review and meta-analysis published last year in PLoS Medicine (Norman et al, 2012) has now provided a better understanding of the association between exposure to physical abuse, emotional abuse, and neglect in childhood and mental and physical health outcomes in later life.

Methods

The authors conducted a systematic review of all publications in Medline, EMBASE and PsychINFO databases up to the end of June 2012 that investigated the relationship between child physical abuse, emotional abuse, or neglect and any health outcome. Importantly (and unusually for such reviews) articles in languages other than English were included (and translated). From this search, 124 studies were eligible for inclusion, the vast majority (112) from Western, English-speaking countries. Only 16 were prospective, longitudinal studies.

Results

Emotionally abused children had a 3-fold higher risk for developing depression and anxiety

The strongest evidence was for mental disorders such as depression and anxiety. Emotionally abused children had a three-fold higher risk for developing these disorders (Depression; OR 3.06 [95% CI 2.43-3.85], Anxiety; OR 3.21 [95% CI 2.05-5.03]), but both physically abused (Depression; OR 1.54 [95% CI 1.16-2.04], Anxiety; OR 1.51 [95% CI 1.27-1.79]) and neglected (Depression; OR 2.11 [95% CI 1.61-2.77], Anxiety; OR 1.85 [95% CI 1.25-2.73]) children also had significantly elevated risk, with evidence that those experiencing more severe abuse or neglect being at the greatest risk.

Similar effects of non-sexual child maltreatment were found on risk for eating disorders, drug and alcohol use, and suicidal behaviour.

The only physical health outcome for which there was strong evidence for an association with non-sexual child maltreatment was sexually-transmitted diseases and/or risky sexual behaviour. These outcomes were around 1.7 times more likely in those with a history of abuse.

Evidence for an association with chronic diseases such as stroke, obesity, arthritis and headache/migraine was weak and inconsistent.

Strengths and limitations

The main limitation of this meta-analysis is its reliance on retrospective data

The authors did do an excellent job of finding all the relevant evidence, and used a statistical model that allowed them to weight each study by quality. However, the main limitation to this meta-analysis is its reliance on retrospective data. Only 13% of the included studies were prospective in design (and nearly two-thirds of these are based on the same longitudinal cohort), which is likely to have introduced significant variability in the assessment and description of maltreatment. This means that the reported relationships may not be as specific as it appears.

Conclusion

The authors assert that:

There was robust evidence of significant associations between exposure to non-sexual child maltreatment and increased likelihood of a range of mental disorders, suicide attempts, drug use, STIs, and risky sexual behaviour.

In this regard, neglect seems to be as harmful as physical and emotional abuse, and this emphasises the need for preventive strategies and for making such prevention a political priority globally.

Stephen Wood is Professor of Adolescent Brain Development and Mental Health in the School of Psychology at the University of Birmingham. He has a particular interest in the development of severe mental illness, using a variety of techniques to predict those at greatest risk.

[…] for The Mental Elf, I reported on a systematic review and meta-analysis of the association between exposure to childhood maltreatment and later mental and physical ill health. That demonstrated a link between physical abuse, emotional abuse, and neglect, with poor mental […]